Then you also have to build 2 full floors and can forget the idea of an attic with knee wall 1.80 m.
I see it differently: according to the Baden-Württemberg state building code the definition of a full floor (excerpt) applies: "Not full floors are [...] 2. uppermost floors, where the height of 2.3 m is present over less than three quarters of the floor area of the floor below." This means conversely: if 2.3 m and more are present over more than three quarters of the floor area of the floor below, a full floor is reached. I now assume that the upper floor has the same floor area as the floor below – so I can use its own floor area as a reference. The area between knee wall height (in the example 1.8 m) and the reaching of the 2.3 m mark must now make up less than one quarter. Starting from a gable roof, a house depth of 7 m (between the exterior walls) is sufficient for this, if I’m not mistaken. That should be achievable (?)
Correct, that is how a construction company and a building planner also explained it to me. With a relatively high knee wall of 1.8m (which we wanted anyway), at the size we are aiming for, it is considered a full story. So that should not be an obstacle.
However, 45 degree DN could potentially conflict with the allowed ridge height.
For that, you then have an attic with a room height of... now I would have to calculate, it's still too early for me (in any case, what the OP doesn't necessarily want).
45 degree pitch might possibly conflict with the permitted ridge height.
That would then give you an attic with a room height of... now I would have to calculate, but it's still too early for me (in any case, something the OP doesn't necessarily want).
Nothing has been mentioned about ridge height so far.
But the 1.80 m is not fixed either. Over 30 degree pitch is planned, plus 2 VG... it will work out :)